Marine spatial planning (MSP) is the process of analyzing and allocating ocean space for specific uses to achieve specified ecological, economic, and social objectives. Increasingly considered to be the most promising and effective approach to address the myriad of pressures on ocean resources, effective MSP is based on sound science. As governments begin to embrace MSP, they face these initial questions: What baseline data (i.e., ecological, socioeconomic) are needed? What information already exists and what information must be obtained? What is the best way to synthesize the information? What tools exist for mapping the data? Speakers will highlight the major types of scientific information needed for marine spatial planning, identify approaches to synthesize the information, and present recent case studies of such efforts.